A Civil Engineering Success :: essays research papers

Civil engineer History and HeritageU.S. 20 Iowa River BridgeThe Iowa River Bridge on Highway U.S.20 was built in such(prenominal) a way that it not only was able to expand the at one time two driveway blacktop roads into a four lane highway, but also to keep environmental impacts of construction and existence of the twain to a minimum. The $21 million dollar link up consists of two 12.0 m wide beautify structures that each contain five spans of 92 m. These clothe structures are made from erecting a weathering steel I-Girder superstructure. Each deck structure will consist of a 230 mm concrete slab with a 38 mm low-slump concrete wearing course supported by a system of four 3450 mm deep I-girders spaced at 3600 mm centers(1). The support for these structures will be cast-in-place reinforced concrete grounding units. These units consist of two column bents ranging in heights of 20 m to 38 m, and are founded on drilled shafts or driven H-Piles. Engineering SuccessThe constructi on method social occasiond on this bridge is the send-off of its kind in the United States on a steel I-girder highway. The bridge was constructed by a launch erection method in sanctify to avoid damaging its surroundings. This method allowed for large steel portions of the structure to be assembled on large rollers behind one of the bridge abutments and then pushed from docking facility to pier with the use of hydraulic thrusts (or pulling with motors and cables). This area is one of few woodlands left in Iowa, and by doing intensive research Engineers were able to mystify their goal while leaving as much of the natural surroundings unaffected as possible. Lessons LearnedAs stated earlier, this was the first use of this construction method and therefore a lot of lessons came from this erection of this bridge. Among these were loosely environmental concerns. The reason this method was necessary is due to all of the environmental concerns through the Iowa Greenbelt, which is h ome to a number of endangered animals, plants and aquatic life. other aspect of the bridge that the environmental issues affected was the timeline. This included a wintertime shut-down for a little over 5 months due to the eagles roost, as well as the need to shut down some(prenominal) time noise or activities seemed to disrupt the eagles roosting habits.